How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask AMEDEE Your Own Question
Category: Chevy
Satisfied Customers: 26626
Experience:  ASE certified tech ADVANCED LEVEL SPECIALIST. Wisconsin certified emissions state inspector
Type Your Chevy Question Here...
AMEDEE is online now
A new question is answered every 9 seconds

Have 2003 trailblazer, 6 in-line 4-speed auto. generally

Customer Question

have 2003 trailblazer, 6 in-line 4-speed auto.
generally runs great. If traveling @ 50-60 mph, then press throttle slightly I get sputtering and chugging... similar thing happens when running @ 60-70, then road changes from flat to slightly uphill. Pressing throttle a lot, down shifts as expect. Pressing throttle slightly similar sputtering and chugging... think it can't decide to downshift or not.
Submitted: 1 year ago.
Category: Chevy
Expert:  AMEDEE replied 1 year ago.

Hello and welcome! My name is ***** ***** I can assist you with your question. Without looking at the vehicle myself it is hard to say what is going on. However, I can tell you my experience as to what could be wrong causing this issue you are explaning. First thing is the variable valve timing solenoid. This solenoid could be sticking intermittantly causing this slight hesitation you are talking about. Another common cause would be bad tune up parts or even a bad oxygen sensor.

Expert:  AMEDEE replied 1 year ago.

There are also PCM updates to help with this sort of thing as well. Cleaning the throttle body may help and checking the electronic fan clutch might be worth looking into. (you can disconnect the connector going to it and then retest). Some fan control complaints can be misinterpreted as a running problem.

Expert:  AMEDEE replied 1 year ago.

Another possible cause would be the mass air flow sensor. Ths computer uses this sensor for injector pulse width and it is a very important sensor. You can try cleaning it to see if that helps but it may need to be replaced.